// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_RESOURCES_UI_RESOURCE_MANAGER_H_
#define CC_RESOURCES_UI_RESOURCE_MANAGER_H_

#include <unordered_map>
#include <vector>

#include "base/macros.h"
#include "cc/base/cc_export.h"
#include "cc/resources/scoped_ui_resource.h"
#include "cc/resources/ui_resource_request.h"

namespace cc {
class UIResourceRequest;

class CC_EXPORT UIResourceManager {
public:
    UIResourceManager();
    virtual ~UIResourceManager();

    // CreateUIResource creates a resource given a bitmap.  The bitmap is
    // generated via an interface function, which is called when initializing the
    // resource and when the resource has been lost (due to lost context).  The
    // parameter of the interface is a single boolean, which indicates whether the
    // resource has been lost or not.  CreateUIResource returns an Id of the
    // resource, which is always positive.
    virtual UIResourceId CreateUIResource(UIResourceClient* client);

    // Deletes a UI resource.  May safely be called more than once.
    virtual void DeleteUIResource(UIResourceId id);

    virtual gfx::Size GetUIResourceSize(UIResourceId id) const;

    // Methods meant to be used only internally in cc ------------

    // The current UIResourceRequestQueue is moved to the caller.
    std::vector<UIResourceRequest> TakeUIResourcesRequests();

    // Put the recreation of all UI resources into the resource queue after they
    // were evicted on the impl thread.
    void RecreateUIResources();

private:
    struct UIResourceClientData {
        UIResourceClient* client;
        gfx::Size size;
    };

    using UIResourceClientMap = std::unordered_map<UIResourceId, UIResourceClientData>;
    UIResourceClientMap ui_resource_client_map_;
    int next_ui_resource_id_;

    using UIResourceRequestQueue = std::vector<UIResourceRequest>;
    UIResourceRequestQueue ui_resource_request_queue_;

    DISALLOW_COPY_AND_ASSIGN(UIResourceManager);
};

} // namespace cc

#endif // CC_RESOURCES_UI_RESOURCE_MANAGER_H_
